5: Mono Lake’s unique water

Have you ever gone for a swim in Mono Lake? The lake is 2.5 times saltier than the ocean so you can easily kick back and float in the water. But why is this a salt-water lake? Because Mono does not have an outlet stream, water flows into the lake, but can only leave through evaporation; therefore, in this terminal lake, as pure water evaporates, salts and minerals that flow into the lake get more concentrated over time.

David Gaines, founder of the Committee, floating in Mono Lake.

Put your hand in the water and rub your fingers together. What does the water feel like? Slimy? Maybe slippery or soapy? Mono Lake has very unusual water chemistry and is full of carbonates, sulfates, and chlorides. These minerals give the lake a relatively high pH of about 10. This high alkalinity is why there are no fish in Mono Lake, though there is fossil evidence showing that fish once swam in Mono Lake when the water chemistry was much different.

Follow the shoreline and look for swarming alkali flies near the water.